Return-Path: Received: from ms-smtp-01.southeast.rr.com ([24.93.67.82] verified) by logan.com (CommuniGate Pro SMTP 4.1.4) with ESMTP id 2603186 for flyrotary@lancaironline.net; Thu, 25 Sep 2003 08:28:00 -0400 Received: from o7y6b5 (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-01.southeast.rr.com (8.12.5/8.12.2) with SMTP id h8PCKT0R001590 for ; Thu, 25 Sep 2003 08:20:31 -0400 (EDT) Message-ID: <005401c38360$2f135100$1702a8c0@WorkGroup> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: DIE the short Answer Date: Thu, 25 Sep 2003 08:26:02 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0051_01C3833E.A7CF5660" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 This is a multi-part message in MIME format. ------=_NextPart_000_0051_01C3833E.A7CF5660 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable > Charlie, > <... Or have I completely missed the point & the goal is actually to = tune for air > temperature? ...> > Actually, if I'm not badly mistaken, that's exactly what we're tuning = for. I > haven't done any of the studying that Ed has, .... But a lot of the = talk here turns on > "resonance" and "wave pulses" and what not. Resonance is sound. The = pulses > we're discussing are sound. Sound travels at the speed of sound. =20 . SNIP . If we design for > relatively mild temperatures, say 60F, we can cruise comfortably at = 8k' - 10k' > during the summer. Just climb until the intake charge matches the = design intake > temperature and cruise there. In winter, we can turbocharge, = adjusting the > wastegate to achieve the desired intake temps. We might have to = cruise at 15k' > in winter, adjusting boost to achieve the intake temps we need for = resonance. > SNIP . Runner length is not the only variable. Perhaps > there's some advantage to looking at them all >=20 > Or perhaps this whole thing is just a remarkably extended brain = fart... Jim S. >=20 Hey, hey, Jim. Watch who's work you are calling an "remarkably extended = brain fart.."{:>) Right, except with the EDDIE, resonance does not enter the picture, if = this definition of resonance is anywhere close: Resonance [n] a = vibration of large amplitude produced by a relatively small vibration = near the same frequency of vibration as the natural frequency of the = resonating system. Resonance is a factor in most of the "tuning" = theories such as the "Organ Pipe" and Helmholtz Resonance theoreis, but = not in the EDDIE. However, the speed of sound is a factor as you indicate, which is = dependent on the ..Lets see if I got the lesson right ... dependent on = the TEMPERATURE of the air in the intake manifold --Yep! think I've got = that relationship down now. Changes in manifold air temperature do perturbate the EDDIE RPM point = as you said. However, it turns out there is another factor (in addition = to RPM) that is much more dominate (don't ask - won't reveal, confirm = or deny until Shady Bend {:>)) in determining EDDIE rpm than = temperature. Don't misunderstand, temp does play a non-minor role, for = example a 50F drop in temp would equate to roughly 2.5" (port-port) = decrease in length needed in your intake, IF you were going to hold the = EDDIE rpm at its design point. The reason, of course, is that since the = speed of sound drops with the decrease in temperature, to maintain the = same timing you would need to effectively shorten the manifold length to = compensate - IF you were trying to maintain the design EDDIE point. There is always the possibility that there is a major flaw in my = analysis or synthesis of the governing equations - that I am just = oblivious to. To date, I've only showed it to one other person and = nothing obviously incorrect jumped out to them. However, I intend to = have Tracy Crook review it at SERFI next weekend, so if you never hear = from me again after that you can draw your own conclusions {:>) =20 I mean how much would you trust the work of a guy that tried to throw = "density" into the speed of sound equation?? Actually, I used the = correct formula for speed and temp, but thought that the reason the = speed changed with temp was because the density of air changed with = temp. But, the EDDIE provides an answer for every strange thing I've = noticed about power production with my installation - and besides it = stacks up well, when compared to what little concrete we think we know = from Mazda about their use of the effect in the rotary.=20 Ed Anderson ------=_NextPart_000_0051_01C3833E.A7CF5660 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

> Charlie,
> <... Or have I = completely=20 missed the point & the goal is actually to tune for air
> = temperature?=20 ...>
> Actually, if I'm not badly mistaken, that's exactly what = we're=20 tuning for.  I
> haven't done any of the studying that Ed = has, =20 .... But a lot of the talk here turns on
> "resonance" and = "wave=20 pulses" and what not.  Resonance is sound.  The pulses
> = we're=20 discussing are sound.  Sound travels at the speed of sound. =20
 
.   SNIP
 
.  If we design for
> = relatively mild=20 temperatures, say 60F, we can cruise comfortably at 8k' - 10k'
> = during=20 the summer.  Just climb until the intake charge matches the design=20 intake
> temperature and cruise there.  In winter, we can=20 turbocharge, adjusting the
> wastegate to achieve the desired = intake=20 temps.  We might have to cruise at 15k'
> in winter, = adjusting boost=20 to achieve the intake temps we need for resonance.
> =20 SNIP
 
.  Runner length is not the only=20 variable.  Perhaps
> there's some advantage to looking at = them=20 all
>
> Or perhaps this whole thing is just a remarkably = extended=20 brain fart... Jim S.
>
Hey, hey, Jim. Watch who's work = you are=20 calling an "remarkably extended brain fart.."{:>)
 
Right, except with the EDDIE, resonance = does=20 not enter the picture, if this definition of resonance is anywhere=20 close:  Resonance [n]  a vibration of large = amplitude=20 produced by a relatively small vibration near the same frequency of = vibration as=20 the natural frequency of the resonating system.  = Resonance is=20 a factor in most of the "tuning" theories such as the "Organ Pipe" and = Helmholtz=20 Resonance theoreis, but not in the EDDIE.

However, the speed of sound is a factor as you = indicate, which=20 is dependent on the ..Lets see if I got the lesson right ... dependent = on the=20 TEMPERATURE of the air in the intake manifold --Yep! think I've got that = relationship down now.
 
Changes in manifold air =  temperature do=20 perturbate  the EDDIE RPM point as you said.  However, it = turns out=20 there is another factor (in addition to RPM)  that is = much more=20 dominate (don't ask - won't reveal, confirm or deny until = Shady Bend=20 {:>)) in determining EDDIE rpm than temperature.  Don't=20 misunderstand, temp does play a non-minor role, for example a 50F drop = in temp=20 would equate to roughly 2.5" (port-port) decrease in length = needed in=20 your intake,  IF you were going to hold the EDDIE rpm at its = design=20 point. The reason, of course, is that since the speed of sound = drops with=20 the decrease in temperature, to maintain the same timing you would need = to=20 effectively shorten the manifold length to compensate - IF you were = trying to=20 maintain the design EDDIE point.
 
There is always the possibility that = there is a=20 major flaw in my analysis or synthesis of the governing equations - that = I am=20 just oblivious to.  To date, I've only showed it to one other = person and=20 nothing obviously incorrect jumped out to them.  However, I intend = to have=20 Tracy Crook review it at SERFI next weekend, so if you never hear from = me again=20 after that you can draw your own conclusions {:>) 
 
I mean how much would you trust the = work of a guy=20 that tried to throw "density" into the speed of sound = equation?? Actually,=20 I used the correct formula for speed and temp, but thought that the=20 reason the speed changed with temp was because the density of = air=20 changed with temp.
 
 But, the EDDIE =  provides an=20 answer for  every strange thing I've noticed about power = production=20 with my installation - and besides it stacks up well, when compared to = what=20 little concrete we think we know from Mazda about their use of the = effect in the=20 rotary. 
 
 
 
Ed Anderson
 
 
 
 
 
 
 
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